This invention relates to power frequency converters and, more particularly, to circuitry for providing AC power at a frequency which is a fraction of the input power frequency.
When generating electricity utilizing a magneto driven by a gasoline engine, the output frequency of the magneto is a function of the speed of the gasoline engine. Typically, gasoline engine driven portable electric generators are designed to provide a 600 hertz magneto output. To make the output of the generator compatible with standard electric appliances, the frequency of the generator must be reduced by a factor of 10 down to 60 hertz. It has been found that the actual wave shape of the resultant output power is not important so long as the wave shape is symmetrical and has no DC component.
Prior art attempts to change the frequency have not proved entirely satisfactory. Many of these circuits utilize a separate magneto winding to power the conversion circuitry. In addition, many of these circuits consume an appreciable amount of power, limiting the power available to the load. Furthermore, sensitivity to load power factor and load generated noise has proven to be a problem.
It is therefore an object of this invention to provide new and improved circuitry for power frequency conversion.
Another object is to provide power conversion circuitry for converting the 600 hertz output of a gasoline engine driven magneto to 60 hertz.
A further object is to provide power frequency conversion circuitry having reduced power requirements.
Still another object is to provide power frequency conversion circuitry which is insensitive to load power factor or load generated noise.